I have been trying to have this thing working for over a week - getting quite frustrated... I have watched every video, read every thread... Thing is, seems to me that no body out there has the same CPU/MB/RAM combo so can't find the optimal O/C settings for my setup.
I have tried incremental steps, but constant freezing past 3.9Mhz ??!!!!! I've tried through bios, and even through AsusAI suite... I have done it all... Up the voltage, disable power saving options, tried playing around with the multipliers and frequencies... nothing seems to allow me to go past the 3.9 mark.
Even more sad, the only way it gets to 3.9mhz mark is with the automated 'Optimal Mode' in the bios EZ-mode... But when I start from there and deactivate settings and up the multiplier and voltages, it craches again... URGH.
I have a FX-8120 and have mine set to 4GHz with just a 20x multiplier no over voltage and only Cool and Quiet disabled. With a FX-8150 you should be able to hit at least 4GHz with just a multiplier overclock.
Even I was facing the same problem with my FX-8150 on ASUS M5A97 R2.0 /w Corsair Vengeance 1600MHz stock cooler & WD Caviar 500GB Hard Disk..Whenever I overclocked my CPU above 3900MHz It used to occasionally freeze..But now my my CPU is overclocked at 4000MHZ (200MHz x20) and it's smooth as butter..problem is with Win7..I had Win7 Ultimate but when I upgraded to Win8 and upgraded my BIOS with latest BIOS from ASUS website it just works smooth..now I have all Cores always on for any task..be it copy/paste, install/uninstall..everything is now is multithreaded..problem is with task scheduler of windows earlier than Win8 which don't recognize the innovative architecture of FX series and are thus not optimised..Microsoft has a Hotfix for FX series on Win7..use that hotfix..it mi8 just work..good luck bro!!!